Getting this error while starting my robot : Could not load type 'System.Activities.TextExpressionBase`1' from assembly 'UiPath.Workflow, Version=, Culture=neutral, PublicKeyToken=null'

In debugmode robot works perfect.

When i start from orchestrator im getting this error:

Could not load type ‘System.Activities.TextExpressionBase`1’ from assembly ‘UiPath.Workflow, Version=, Culture=neutral, PublicKeyToken=null’.

Hi @keeswirken

check the below thread:


I have enterprise edition


Navigate to Packages on Orchestrator. Here you will see your published packages. Besides it you will have Libraries which will contain all the dependency packages used in the published packages.

There is possibility the package you are mentioned unavailable due to package version.

Another possibility

The dev environment and production environment like Orchestrator and Robot don’t have same version.

Dev environment and packages should be same or compatible version only. If not downgrade to compatible version and re publish the package.

Ashok :slight_smile:

Hi @keeswirken

Try keeping the packages in the latest version by keeping RunTime Rule as Lowest As Applicable. This should work.


Check the version of the robot executor, compare that to the studio version.
I’d wager studio was on 23.10 or higher and robot on 23.4 or lower.